A simple AIEgen photosensitizer with cucurbit[7]uril selective detection amantadine and application in mitochondrion imaging

A simple amantadine fluorescent probe was designed and prepared by the host–guest interactions of CB[7] and AIEgen photosensitizer TPM, and TPM application in mitochondrion imaging. • A simple AIEgen photosensitizer TPM with cucurbit[7]uril self-assembly product fluorescence sensor CB[7]@TPM. • The CB[7]@TPM exhibited highly selective and sensitive detection of amantadine in water and urine solution. • The obtained TPM can specifically stain the mitochondria in living cells and can acted as an efficient photosensitizer that killed cancer cells. In this work, an AIEgen photosensitizer TPM is synthesized and simple strategy for detecting amantadine (AM) in aqueous solutions and urine is proposed by combining cucurbit[7]uril (CB[7]) with TPM. High emission from the aqueous solution is obtained by the interaction of TPM with CB[7], which formed CB[7]@TPM. The 1 H NMR spectra and isothermal titration calorimetry (ITC) results revealed that TPM is encapsulated in CB[7] in both aqueous solution and urine to form a stable 1:1 host–guest inclusion complex of CB[7]@TPM. When AM added to a CB[7]@TPM solution, strong interconnections formed, which occupied the cavity of CB[7] and formed a complex, CB[7]@AM. Based on the significant quenching of the supramolecular complex’s photoluminescence (PL) intensity, a fluorescence method with high sensitivity and selectivity is developed for the determination of AM in aqueous solutions and urine. The limits of detection (LOD) for AM are determined to be 72 nM in aqueous solution and 80.9 nM in urine. Importantly, due to its amphiphilicity and cationic nature, the TPM can specifically stain the mitochondria in living cells and acted as an efficient photosensitizer for killed cancer cells.